It can be anything! An apex, subdomain, or even a URL.

Results forhostmaster.sikawa.com

Logged At	Not Before	Not After	Common Name	Matching Identities	Issuer Name
2022-12-16T18:13:56.58	2022-12-16T17:13:55	2023-03-16T17:13:54	sikawa.com	*.sikawa.com	C=US, O=Let's Encrypt, CN=E1
2022-12-16T18:13:55.791	2022-12-16T17:13:55	2023-03-16T17:13:54	sikawa.com	*.sikawa.com	C=US, O=Let's Encrypt, CN=E1
2022-09-17T15:21:39.806	2022-09-17T14:21:39	2022-12-16T14:21:38	sikawa.com	*.sikawa.com	C=US, O=Let's Encrypt, CN=E1
2022-09-17T15:21:39.349	2022-09-17T14:21:39	2022-12-16T14:21:38	sikawa.com	*.sikawa.com	C=US, O=Let's Encrypt, CN=E1
2022-06-19T11:00:09.521	2022-06-19T10:00:09	2022-09-17T10:00:08	sikawa.com	*.sikawa.com	C=US, O=Let's Encrypt, CN=E1
2022-06-19T11:00:09.264	2022-06-19T10:00:09	2022-09-17T10:00:08	sikawa.com	*.sikawa.com	C=US, O=Let's Encrypt, CN=E1